Aim. To measure the attitude toward plagiarism of scientists in biomedicine. To evaluate the intent to plagiarize based on positive and negative attitude and frequency of plagiarism based on subjective norms. To determine the differences in attitudes between younger researchers with less experience and older researchers with more experience considering the sociodemographic characteristics, academic success and personality traits. Participants and Methods. The survey study was conducted during years 2012 th and 2013th. Participants were 177 scientists, 131 research fellows and 46 authors who send their articles to Croatian Medical Journal (CMJ). Scientists fulfilled three questionnaires: The Attitude Toward Plagiarism, The Dark Triad D3-27 and The social desirability scale. The questionnaires were available on-line through SurveyMonkeyTM web service. Results. The attitude towards plagiarism was moderate, 58±16, positive attitude was 25±8, negative attitude was 30±4 and subjective norm for plagiarism was 21±5. The incidence of plagiarism has been estimated from 32% to 46%, self-plagiarism from 26% to 32%, and 2% of respondents admitted plagiarism. Scientists with less published papers indexed in Current Contents/Science Citation Index Expanded (CC/SCIE) data base (P<0.001) and low levels of Machiavellianism (P=0.050) were less prone to plagiarize, but scientists with a higher level of psychopathy were more prone to plagiarize (P=0.016). Scientists from Croatia had significantly higher negative attitude compared to scientists from other countries (P=0.005). CMJ authors were more prone to plagiarize than research fellows (P<0.001) in despite of socio-demographic factors, academic success and personality traits. Predictors of plagiarism were psychopathy for negative attitude (8.41%) and subjective norm (3.61%) and Machiavellianism for positive attitude (2.56%).The predictor of negative attitude was also the country of provenience (2.56%). The research group was the moderator between psychopathy/Machiavellianism and the attitude towards plagiarism, reducing the contribution of psychopathy, and enhancing the contribution of Machiavellianism. Social desirable responding was high. Conclusions. Propensity to plagiarism was moderate to low , but given the high propensity of socially desirable responding , the tendency can be interpreted as moderate. Predictors of the attitude towards plagiarism were psychopathy and Machiavellianism. Plagiarism can be predicted in case of a high degree of psychopathy and incentive less environment, visible from low negative attitude, in case of high Machiavelism present in positive attitude and in case of lack of moral values as a predictor of high subjective norm.